The present invention relates to a method of calibrating the mass of identical and interchangeable components intended to be mounted at the periphery of a rotor, in particular of a fan in a turbomachine such as a turbojet or a turboprop.
The air flow path is delimited internally at the inlet of the fan by elongate platforms which are arranged between the roots of the fan blades and fastened to the rotor of the fan.
These platforms are identical and interchangeable components which must have the same mass, with a low tolerance which may be less than a gram, for example.
The manufacture of these platforms generates a relatively wide spread in the mass, thus making it necessary to calibrate the mass to compensate for this spread.
In practice, one solution consists in weighing each platform and in adhesively bonding at least one resin weight or elastomer weight in a longitudinal cavity in the inner face of the platform so as to compensate for a deficit in mass with respect to a predetermined value.
The platforms are complex in shape and the operation of adhesively bonding the weights is carried out by hand. The addition of one or more weights modifies the position of the center of gravity of the platform, which may cause the platform to tilt during operation about the points where it is fastened to the rotor, resulting in separations of the air stream with a deterioration in the engine performance.
The use of these weights also makes it necessary to procure and store these components, and it is required to fasten them carefully using an adhesive.